This invention relates to a method and an apparatus for detaching fiber tufts from textile fiber bales such as cotton bales, chemical fiber bales or the like, wherein a machine frame, accommodating the detaching device proper, travels back and forth along a fiber bale series. The detaching device which has at least one rapidly rotating detaching (opening) roll is positioned at an inclination with respect to the horizontal direction of travel and in this manner detaches the fiber bales along a similarly inclined top surface of the bale series. The fiber bales are supported on a bale transporting device, such as a conveyor belt which is moved stepwise unidirectionally in such a manner that the detaching depth for each pass is determined by the horizontal feed performed with the bale transporting device.
According to a known method, the downstream end of the bale series (as viewed in the direction of horizontal bale feed by the bale transporting device) having the inclined detaching surface has the configuration of a truncated wedge and the frontal boundary of the bale series has a predetermined height. In this manner there is obtained in front of the end face a free space where fiber material detached by the opening roll falls at the end of a working pass. Because of the distance between the detaching roll and the conveyor belt, during feed motions of the conveyor belt, disadvantageously a significant amount of fiber material passes through the remaining opening (intermediate space) and subsequently falls onto the floor from the conveyor belt. Such fiber tufts have to be subsequently removed from the floor. A vertical compression of the terminal zone of the truncated wedge under high pressure cannot be performed because the fiber bales are already in a significantly compressed state and such additional compression would cause a disadvantageous clogging and a more difficult penetration of the detaching roll which could lead to operational disturbances. Also, a more complex control would be needed. In order to be able to work on the frontal end of the truncated wedge over its entire height, the detaching device is, for working on the frontal face, conventionally moved beyond the outermost boundary of the bale series. This causes disadvantageous tearing of the fiber tufts from the fiber bales, and the fiber tufts fall loosely on the floor; consequently, measures must be taken for a removal of such a material. It is a further disadvantage of known arrangements that the motion of the detaching device beyond the end face of the fiber bale series constitutes an idle run (that is, a time loss) during which no fiber tufts are detached from the fiber bales. Also, providing the additional space for such an idle run has structural drawbacks.